Cho \(\displaystyle\int\limits_1^3f(x)\mathrm{\,d}x=3\) và \(\displaystyle\int\limits_1^3g(x)\mathrm{\,d}x=4\), khi đó \(\displaystyle\int\limits_1^3\left[4f(x)-g(x)\right]\mathrm{\,d}x\) bằng
| \(16\) | |
| \(8\) | |
| \(11\) | |
| \(19\) |
Chọn phương án B.
\(\begin{align*}\displaystyle\int\limits_1^3\left[4f(x)-g(x)\right]\mathrm{\,d}x&=4\displaystyle\int\limits_1^3f(x) \mathrm{\,d}x-\displaystyle\int\limits_1^3 g(x)\mathrm{\,d}x\\
&=4\cdot 3-4=8.\end{align*}\)